Types, Features, And Configurations Of Digital I/O Ports; Types And Features Of Digital Ports - NEC PD750004 User Manual

µPD750008 USER'S MANUAL

5.1.1 Types, Features, and Configurations of Digital I/O Ports

Table 5-1 lists the types of digital I/O ports.
Figures 5-2 to 5-6 show the configurations of the ports.
Port name
(symbol)
PORT0 4-bit I/O
PORT1
PORT3 Note 1 4-bit I/O
PORT6
PORT2
PORT7
Note 1
PORT4 4-bit I/O
Note 1
PORT5 (N-ch open-drain; units of 4 bits. Ports 4 and 5 can be
can withstand
*
13V)
PORT8 2-bit I/O
Notes 1. Can directly drive the LED.
2. Only for the µPD75P0016.
3. The µPD75P0016 does not have a mask option and cannot be connected with a pull-up resistor.
*
P10 is also used as an external vectored interrupt input pin. This input is provided with a noise eliminator.
(See Section 6.3 for details.)
When the RESET signal is generated, output latches of ports 2 to 8 are cleared to 0 and the output buffer
is turned off so that these ports are in the input mode.
68
Table 5-1. Types and Features of Digital Ports
Function Operation and feature
Allows read and test at any timeregard
less of the operation modes of another
functions assigned to these pins.
Allows input or output mode setting bit
by bit.
Ports 6 and 7 can be paired, allowing
data I/O in units of 8 bits. Allows input
or output mode setting in units of 4 bits.
Allows input or output mode setting in
paired, allowing data I/O in units of
8 bits.
Allows input or output mode setting in
units of 2 bits.
Remarks
Also used as INT4, SCK, SO/SB0,
and SI/SB1.
Also used as INT0 to INT2 and
TI0.
Also used as MD0 to MD3
Also used as KR0 to KR3.
Also used as PTO0, PTO1, PCL,
and BUZ.
Also used as KR4 to KR7.
Whether to use pull-up resistors
can be specified bit by bit with a
Note 3
mask option .
Note 2 .